Semiconductor Electrochemistry for Clean Energy Conversion and Storage

Abstract

Semiconductors and the associated methodologies applied to electrochemistry have recently grown as an emerging field in energy materials and technologies. For example, semiconductor membranes and heterostructure fuel cells are new technological trend, which differ from the traditional fuel cell electrochemistry principle employing three basic functional components: anode, electrolyte, and cathode. The electrolyte is key to the device performance by providing an ionic charge flow pathway between the anode and cathode while preventing electron passage. In contrast, semiconductors and derived heterostructures with electron (hole) conducting materials have demonstrated to be much better ionic conductors than the conventional ionic electrolytes. The energy band structure and alignment, band bending and built-in electric field are all important elements in this context to realize the necessary fuel cell functionalities. This review further extends to semiconductor-based electrochemical energy conversion and storage, describing their fundamentals and working principles, with the intention of advancing the understanding of the roles of semiconductors and energy bands in electrochemical devices for energy conversion and storage, as well as applications to meet emerging demands widely involved in energy applications, such as photocatalysis/water splitting devices, batteries and solar cells. This review provides new ideas and new solutions to problems beyond the conventional electrochemistry and presents new interdisciplinary approaches to develop clean energy conversion and storage technologies. Graphic Abstract

Nickel-iron nanoparticles encapsulated in carbon nanotubes prepared from waste plastics for low-temperature solid oxide fuel cells

“…The limited performances of LT-SOFCs are attributed to several factors, such as low ionic conductivity (<0.1 S cm À1 ) of conventional electrolyte materials such as yttria-stabilized zirconia (YSZ), as well as sluggish electrode reactions resulting from the low catalytic activity (Alipour et al, 2022;Fan et al, 2022;Zhu et al, 2021a). The incorporation or in situ manufacture of active nanocomponents to form the nanocomposite might be a solution to these problems (Mushtaq et al, 2021b;Tabassum et al, 2019).…”

A-site deficient semiconductor electrolyte Sr1−xCoxFeO3−δ for low-temperature (450–550 °C) solid oxide fuel cells

“…An important benet of semiconducting materials is the high ionic conductivity without short-circuiting issues. 11,12 Also, metal oxides, perovskites, uorite, and layered structure such as TiO 2 , ZnO, CeO 2, and NCAL (Ni 0.8 Co 0.15 Al 0.05 LiO 2 ) falls under the semiconducting materials with enhanced electrical properties. [13][14][15][16] Semiconductor ionic membranes have played an important role in improving the performance of fuel cell devices.…”

“…[13][14][15][16] Semiconductor ionic membranes have played an important role in improving the performance of fuel cell devices. 12 High performance is due to the heterojunction between the semiconductor and ionic conductor, which further forms a space charge region constituting BIEF (built-in electric eld). 17 For example, SFT-SDC (SrFe 0.75 Ti 0.25 O 3Àd -Sm 0.25 Ce 0.75 O 2Àd ) is an efficient electrolyte delivering high fuel cell performance and high ionic conductivity, which can be explained through the formation of a heterojunction between the semiconductor SFT and ionic conductor SDC.…”

CoN5 Sites Constructed by Anchoring Co Porphyrins on Vinylene‐Linked Covalent Organic Frameworks for Electroreduction of Carbon Dioxide

“…Pyrolysis of Metal and N-contained complex precursors was most common approach to construct metal-N X sites in catalysts. [14][15][16][17][18][19][20] However, the disordered pores and uncontrollable skeletons of the carbon support hinder us to precisely modulate the density and location of active sites.Covalent organic frameworks (COFs), are a class of crystallinity and porous polymers, have shown various application owing to their designable skeletons, ordered porous channels, controllable porous environment, and excellent chemical and thermal stability. [21][22][23][24][25][26][27][28][29][30][31][32][33][34] Meanwhile, the one-dimensional pore channels of COFs facilitated ions transport, and the active Co sites were well distributed in the knots by using Co-porphyrins or phthalocyanines building units Developing effective electrocatalysts for CO 2 reduction (CO 2 RR) is of critical importance for producing carbon-neutral fuels.…”

“…Pyrolysis of Metal and N-contained complex precursors was most common approach to construct metal-N X sites in catalysts. [14][15][16][17][18][19][20] However, the disordered pores and uncontrollable skeletons of the carbon support hinder us to precisely modulate the density and location of active sites.…”